diff options
| -rw-r--r-- | include/linux/perf_event.h | 7 | ||||
| -rw-r--r-- | kernel/hw_breakpoint.c | 8 | ||||
| -rw-r--r-- | kernel/perf_event.c | 23 |
3 files changed, 29 insertions, 9 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 2ebfc9a..97965fa 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -536,6 +536,12 @@ struct hw_perf_event { struct { /* breakpoint */ struct arch_hw_breakpoint info; struct list_head bp_list; + /* + * Crufty hack to avoid the chicken and egg + * problem hw_breakpoint has with context + * creation and event initalization. + */ + struct task_struct *bp_target; }; #endif }; @@ -693,6 +699,7 @@ struct swevent_hlist { #define PERF_ATTACH_CONTEXT 0x01 #define PERF_ATTACH_GROUP 0x02 +#define PERF_ATTACH_TASK 0x04 /** * struct perf_event - performance event kernel representation: diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index 3b714e8..2c9120f 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -113,12 +113,12 @@ static unsigned int max_task_bp_pinned(int cpu, enum bp_type_idx type) */ static int task_bp_pinned(struct perf_event *bp, enum bp_type_idx type) { - struct perf_event_context *ctx = bp->ctx; + struct task_struct *tsk = bp->hw.bp_target; struct perf_event *iter; int count = 0; list_for_each_entry(iter, &bp_task_head, hw.bp_list) { - if (iter->ctx == ctx && find_slot_idx(iter) == type) + if (iter->hw.bp_target == tsk && find_slot_idx(iter) == type) count += hw_breakpoint_weight(iter); } @@ -134,7 +134,7 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp, enum bp_type_idx type) { int cpu = bp->cpu; - struct task_struct *tsk = bp->ctx->task; + struct task_struct *tsk = bp->hw.bp_target; if (cpu >= 0) { slots->pinned = per_cpu(nr_cpu_bp_pinned[type], cpu); @@ -213,7 +213,7 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type, int weight) { int cpu = bp->cpu; - struct task_struct *tsk = bp->ctx->task; + struct task_struct *tsk = bp->hw.bp_target; /* Pinned counter cpu profiling */ if (!tsk) { diff --git a/kernel/perf_event.c b/kernel/perf_event.c index b21d06a..856e20b 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -5255,9 +5255,10 @@ unlock: */ static struct perf_event * perf_event_alloc(struct perf_event_attr *attr, int cpu, - struct perf_event *group_leader, - struct perf_event *parent_event, - perf_overflow_handler_t overflow_handler) + struct task_struct *task, + struct perf_event *group_leader, + struct perf_event *parent_event, + perf_overflow_handler_t overflow_handler) { struct pmu *pmu; struct perf_event *event; @@ -5299,6 +5300,17 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, event->state = PERF_EVENT_STATE_INACTIVE; + if (task) { + event->attach_state = PERF_ATTACH_TASK; +#ifdef CONFIG_HAVE_HW_BREAKPOINT + /* + * hw_breakpoint is a bit difficult here.. + */ + if (attr->type == PERF_TYPE_BREAKPOINT) + event->hw.bp_target = task; +#endif + } + if (!overflow_handler && parent_event) overflow_handler = parent_event->overflow_handler; @@ -5559,7 +5571,7 @@ SYSCALL_DEFINE5(perf_event_open, } } - event = perf_event_alloc(&attr, cpu, group_leader, NULL, NULL); + event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, NULL); if (IS_ERR(event)) { err = PTR_ERR(event); goto err_task; @@ -5728,7 +5740,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, * Get the target context (task or percpu): */ - event = perf_event_alloc(attr, cpu, NULL, NULL, overflow_handler); + event = perf_event_alloc(attr, cpu, task, NULL, NULL, overflow_handler); if (IS_ERR(event)) { err = PTR_ERR(event); goto err; @@ -5996,6 +6008,7 @@ inherit_event(struct perf_event *parent_event, child_event = perf_event_alloc(&parent_event->attr, parent_event->cpu, + child, group_leader, parent_event, NULL); if (IS_ERR(child_event)) |